|
Additional Resources
• Insect ID Guide | • FAQs | • Steward® Successes
Questions and answers about beneficials, pests, and DuPont™ Steward®
insecticide.
Q. Which cotton pests does DuPont™ Steward® insecticide control?
A. Steward® is extremely effective against lepidopteran larvae such as tobacco budworm, cotton bollworm, beet armyworm, fall armyworm, cabbage and soybean looper, as well as some important sucking insect pests, specifically tarnished plant bug (suppression only for lygus hesperus) and cotton fleahopper.
Q. I'm trying to maintain beneficial insects while controlling caterpillar pests and plant bugs. What will Steward® do to beneficials?
A. Steward® is easy on most beneficial predators and parasites*. The key to beneficial insect management with Steward® or any insecticide is scouting, and applications timed early in the pest life cycle to reduce the need for multiple applications. As the insecticidal activity of Steward® is primarily through ingestion of treated foliage, beneficials (predators and parasites) that are not foliage feeders and only have contact with Steward® as a dry residual are not significantly affected. *See product label for specific application instructions.
Q. How can Steward® control tarnished plant bug and cotton fleahopper, yet be safe to sucking predaceous bugs like bigeyed bug and minute pirate bug?
A. The insecticidal activity of Steward® on target pests is the result of ingestion and contact. Once inside the insect, indoxacarb must be bioactivated into its active form to cause mortality. Predators and parisitoids exposed to a dried residual are not impacted because they do not ingest material; tarsal contact restricts the movement of the compound into the insect; and predators and parasitoids are usually less efficient at bioactivating indoxacarb into its active molecule compared to lepidopteran larvae. Some beneficial insects whose behavior allows them to be exposed to indoxacarb by piercing and feeding on treated foliage or to a direct spray at highest labeled rates may be affected, but populations rapidly recover since there are many unexposed individuals. The keys to beneficial insect management with Steward® or any insecticide include scouting, and applications timed early in the pest cycle to reduce the need for multiple applications.
Q. How long can I expect residual control from an application of DuPont™ Steward®?
A. The residual activity of Steward® on cotton appears to be in the range of 5-14 days. Do not confuse residual with spray interval. A key factor for determining the spray interval is the rate of new growth. Early in the growing season, cotton puts on a new terminal and lateral branch node every three days. Thus a five-day spray interval during the bloom to bollset periods may be needed to cover new growth. Late in the season, when foliar feeders are potential pests and new growth is less of a factor, Steward® has provided excellent extended plant protection.
Q. How long after I apply Steward® do I have to wait before can go back into the field without personal protective equipment (PPE)? What PPE do I need when mixing Steward®?
A. The re-entry time for Steward® is 12 hours after treatment. The personal protective equipment for applicators and other handlers is a long-sleeved shirt and long pants, chemical-resistant gloves Category A (such as butyl rubber, natural rubber, neoprene rubber or nitrile rubber) all greater than or equal to 14 mils and shoes, plus socks. For early entry to treated areas that involves contact with treated plants, soil or water, wear: coveralls over long-sleeved shirt and long pants, socks, plus chemical-resistant footwear and chemical-resistant gloves Category A (such as butyl rubber, natural rubber, neoprene rubber or nitrile rubber) all greater than or equal to 14 mils. A Caution" warning symbol is on the label. This signal word is the lowest human hazard signal word issued by the EPA.
Q. Can DuPont™ Steward® be used on Bt cotton?
A. Steward® will have an excellent fit on Bt cotton due to its unique mode of action and mid-season application flexibility, when conservation of beneficials is critical. It is highly effective on bollworm larvae, fall armyworm, beet armyworm and looper, and provides plant bug activity. The novel mode of action of Steward® will provide control of pyrethroid-resistant bollworm.
Q. What is the armyworm complex?
A. The armyworm complex is the group of species that are in the noctuidae family of caterpillars. The common cotton pests include beet, fall, yellow-striped and southern armyworm. Field tests to date indicate that Steward® will control fall armyworm and beet armyworm. The remaining species are currently being evaluated in field trials for potential addition to the label in the future.
Q. Can I tank mix Steward® with another crop protection chemical if needed?
A. Steward® is compatible with common insecticides and herbicides that may be used in cotton, such as DuPont™ Glyphosate, DuPont™ Staple® Plus*, DuPont™ Staple®, Roundup or MSMA. Guidance on mixing order based on formulation type is provided on the Steward® label. Keep in mind that all soluble fertilizer blends have not been tested for compatibility or foliar burn. Steward® has been successfully mixed and applied with registered plant growth regulators such as mepiquat chloride and Pgr IV.
*Where labeled
Q. Can DuPont™ Steward® be used in a chemigation system?
A. Chemigation is prohibited with Steward®.
Q. Do I need to add a surfactant to make Steward® work better?
A. The addition of a surfactant is not required. Steward® contains both an oil carrier and surfactant that provide leaf wetting optimal for crop protection. However, certain conditions (low-use rates, low carrier volumes, increased spray intervals) may exist where the addition of a high-quality surfactant may enhance product performance.
Q. How fast does Steward® work? Will I see insects on the ground in a few hours?
A. Steward® does have contact activity, though its primary mode of action is via ingestion. Steward acts by blocking sodium ion entry into nerve cells. In cases where foliar feeders are devouring treated foliage, you may see initial activity within 4-8 hours. Insects become partially paralyzed, sluggish and uncoordinated. Affected insects, who become dehydrated since feeding is minimized, can often fall off the plant. Mortality generally takes place in 48-72 hours following ingestion. However, feeding stops within 0-4 hours, providing excellent crop protection.
Q. How often do I need to make a Steward® application?
A. It is important to maintain a proper treatment interval and perform close scouting for the cryptic feeders such as bollworm/budworm. The minimum application interval allowed is 5 days. Sequential applications may be required to attain satisfactory control of fall armyworm or beet armyworm, which must feed through the treatment to be affected. This is true for most of the current products. The most significant strength of Steward® is its plant protectant activity, rainfastness and residual. This is best utilized by timely scouting and application scheduling.
For more information. Please contact your local DuPont District Sales Manager or DuPont Crop Protection Retailer for more information about Steward® insecticide from DuPont. And visit our Web site at: www.steward.dupont.com
*Get the latest Adobe Reader® to view and print Adobe PDF files.
*See Steward® label for specific beneficial insects.
Roundup is a registered trademark of Monsanto Company.
Steward® insecticide, Staple® and Staple® Plus herbicides are registered trademarks of E.I. du Pont de Nemours and Company.
|
